517247981 has 2 divisors, whose sum is σ = 517247982. Its totient is φ = 517247980.

The previous prime is 517247959. The next prime is 517248071. The reversal of 517247981 is 189742715.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 420619081 + 96628900 = 20509^2 + 9830^2 .

It is a cyclic number.

It is not a de Polignac number, because 517247981 - 2¹⁸ = 516985837 is a prime.

It is a super-2 number, since 2×517247981² = 535090947697152722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (517247911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 258623990 + 258623991.

It is an arithmetic number, because the mean of its divisors is an integer number (258623991).

Almost surely, 2^517247981 is an apocalyptic number.

It is an amenable number.

517247981 is a deficient number, since it is larger than the sum of its proper divisors (1).

517247981 is an equidigital number, since it uses as much as digits as its factorization.

517247981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 141120, while the sum is 44.

The square root of 517247981 is about 22743.0864440163. The cubic root of 517247981 is about 802.7240374348.

The spelling of 517247981 in words is "five hundred seventeen million, two hundred forty-seven thousand, nine hundred eighty-one".